Power-transmission apparatus



July 8, 1930. J. J. o. RULIANclcH POWER` TRANSMISSION APPARATUS Filed Nov. 20, 1925 IN VEN TOR.

I MAMA Aff/l1 hu' A TTORNEY Patented July s, 193e PATENT orricr. A

`:ronciv 1.o. RULIANCICH, on'fAn'NoLn, rENNsYLvANIA PoWEn-TRANsivrissioN APPARATUS Application led November This invention relates to power transmissionvapparatus andaims to provide means by which a high reduction of speedwith a corresponding increase of torque may be obtained with` a minimum loss of power.

The invention relates particularly to transv- Y mission apparatus of the type in which an in- ,ner gear is given a rotational movement about the axis of an outer gear with which it cooperates, andthe object lof the invention is to provide a practical transmission apparatus of this character which is simple and rugged in construction, so that it may be inanufactured economically and may bev used for a vhigh degree of reduction and to apply heavy ,torques A particular vobject of `the inveny mission apparatus.

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Athe invention and tion is to providefor l a combined positive and frictional engagement of the gears, so that, while positive engaging elements insure an absence of slip at comparatively low speeds,

friction surfaces are' brought forcibly together and relieve the strain on the positive elements at high speeds when high torques are,

applied. A further object of the invention is to counterbalance the centrifugal force of the inner gear about the axis ofthe transmission apparatus, while at the lsame time'leaving this gear free to move outwardly under its centrifugal force so as to bring its friction surface into firm contactk with the friction surface of the outer gear. A still further object of the invention is to provide a simple and rigid form of mounting for the trans- The means by which these and other objects of the invention are attained may best be understood from a detailed description of a .practical transmission apparatus embodying illustrated in the `accom`- panying drawings, in which :-l

Fig. 1 is an axial section of the apparatus; and y v vFigure 2 is a transverse Ysection upon the line 2-2 of Figure 1.,

The transmissionapparatus illustrated has a framework consisting of an approximately cylindrical casing 10, secured to a base 11,

which holds it with its axis horizontal. The

casing is formed of two cup-shaped members 12, 13, whose edges are secured together by 2o, i925. serial No. 70,212.

' for the driving shaft 17.

y The mechanism of the transmission includes a fixed outer gear A formed by the edge portions ofthe cup-shaped members 12, 13, andan inner gear B mounted for revolutionary movement on a supporting member` or cage B2 consisting of two disks B3, B4, secured togetherby bolts Bpassing through large openings B@ in the gear B.v The disc B3 is keyed to the driven shaft 15While the disc B1 is rotatably mounted on the driving shaft 17. The gear B is connected with its supporting cage B2 by three cranksor pairs of links B1, each secured at one end to the gear B by pivots or crank pins B9, and at the other end to the cage B2 by pivots or stub shafts B10. This connection constrainsv the gear B againstrotational movement on its axis With respect to the cage B2, but permits the gear B to have a bodily revolutionary movement about the axis of the cage B2; y The inner and `outer gears A, B are arranged for combined positive and frictional engagement. The outer gear A has a cylin` drical friction surface A1 formed on flanges A2 at the edges of the cups 12, 13. The diameter of this cylindrical surface is the pitch diameter of the outer gear. rlhe bolts A3, by which' the cups 12, 13 are secured together, serve to space the edges of the cups apart so as to leave an open space or recess '1 between the edges of the flanges A2 on which the friction surface A1 is formed. These bolts A3 have their axes in the cylindricalsurface A1, so that one-half-of each bolt projects out from the surface A1, as shown in Fig. 2. Y

The inner gear is provided with a cylindrical friction surface B1 adapted to engage the friction surface A1. l The diameter of this cylindrical surface is the pitch diameter of Vthe inner gear. l surface B1 is a circumferential projection or rib B11 which projects into the space A* between the flanges A2. The friction surface B1 and the rib B11 are cut by transverse grooves B7 which are separated by the .Same

In the middle of the friction distance as the bolts A3, sothat they serve Vt'oembrace the bolts and form a positivedrivi ing connection between the two gears.`

The weight and centrifugalforce of the inner gear B are` counterbalanced by weights B1? formed at theoruter ends ofthe cranks or` inks B8. T'he combined` mass ofthe weights B1? is equal'to that vofthe links and the inner gear.` In order that the centrifugal'force of the inner gear maybefutilized .toforce its-fric# tion surface B1 against the friction surface Al of the outer gear, theapparatus is arranged so that the counterbalanoing cefntrifV ugal force of the weights B12 is not applied jdirectly lto thepinnergear B, but is vapplied greater thanthe pitch radius 'of theouter gear (theamount of the differencefbeing too small to be shown in the drawings), and also, most desir-ably, by providing a yielding convnection Ybetween 4the inner gear` and the weights`l312. Thismay be done by providing l resilientroller bearings B1? between the piv` ots or crankpins B9 and the inner gear B` (as .shown in the drawings) or between the pivots B9 andthe linksB The reqnired`revolutionary movement is given fto the inner by means of ya crank 18 on the inner Yend ofthe driving shaft 17.

' In order to permit the inner gear to move .out

=wardly under `theeffect 4of centrifugal fOrCe, a resilient roller bearing 19is provided between thepin 2O ofthe crank 18 and the innergearLB, and a similar resilient bearing illinay provided forthe driving shaft` 17 itself.

d In the operation of the device,power isappliedto the vdriving,shaft 17 to revolve the inner gear B. As the outer gear A is lixed,

being formed onythe frame-work of the'mechanism, theengagement of theitwo' gearsiresultsingivingthe cageB2 and the driven shaft ,15. rotation at areducedspeedand in the opposite direction from that of the driving,

shaft .17, Thereductionin speed is inthe ratio ofthe difference betweenthediameters of the'two gears to thedia-meter of theinner v, gear. It may `accordingly be @made very v large by tmaking the two.v gears rof nearlyy the `same diameter.l

positive drivingconnectionbetween the two gears 1s. secured by the engagement of the notches'lB7 withthe bolts A3, so that noslip` can occur, reven when lthe driving shaftiis re- *ivolving so slowly that there is flit'tle'or no pressure between thefriction surfaces of the l'gears. when, however, the driving shaft is rotated` at.high.speed,.the inner gear B is forcibly thrown outward by centrifugal force,

- bringing its( friction surface B1 in firm contact vwith thefriction surface A1 of the outer gear. The contact between these surfaces relieves the bolts and grooves A3, B7 of all radial load and also relieves them of all, or a large part of, the 'torque' load as soon as the' friction surfaces become firmly held together Y by centrifugalforce. 1

. The weights B12' counterbalance the cen- `trifugal forceof the inner gearl about the axis Vof the driving and driven shafts, so that the Y gear under its construction of the engaging surfaces of the two gears,4 may be applied to a transmission ,apparatus which is mounted so that the outer Vgear revolves while the cage is heldstationary, or a transmission in whicheither the outer gear or fthe cage may be locked stationary whilel the other. is locked to the driving shaft.

What Iclaim is: Y

inner and outergears, vand means for revolv- 1. -In n transmission apparatus, cooperating ing the inner gear about an axis of the outer gear, and weights arranged to counterbalancethe centrifugal force'of `the inner .gear about .the axis of the outer gear, the inner gear being mounted to move outwardly under the eect of its centrifugal force. y

2. In transmission apparatus, .the Vcombination with anouter gear, an inner gear, the inner gear being mounted for a bodily' revolutionary movement thereof, of weights counterbalancing the weight of the inner gear, and yielding connections between said weights and the inner gear.

13. In transmission apparat-us, the combination with an outer gear, an inner gear, a supporting member therefor, and a plurality of parallel links connecting the inner gear to Vthe supporting member so as topermit bodily revolution of thegear aboutthe axis of the supporting member, of resilient elements. permitting an increase in the effective length of said links, and weights on said links counterbalancing theweight of said gear.`

4Q lTransmission apparatus, comprising a iXed casing,an outer gear iXed in said "cas- Qing, aligned'clriving and driven shafts jour-- naled in the ends of said casing, a single in-` ner gearV cooperating with said outer A gear and Vhaving its center 'eccentrically mounted on saiddriving shaft, means within the casing for transferring rotationalmoveinents of the inner gear to the driven'sh'aft, said inner gear beingmounted to move outwardly under vthe effect 'of its centrifugal force, and means counterbalancing the centrifugal effect of said inner gear on said transferring means.

`5. Transmission apparatus, comprisinga fixed substantially cylindrical casingk whose llO CAI

inner wall provides a gear surface, aligned driving and driven shafts journaled in the ends of said casing, an inner gear cooperating with the gear surface provided by the casing and having its center eccentrically mounted on the driving shaft, and means within the casing for transferring rotational movements of the inner gear to the driven shaft, said means including a support fixed to the driven shaft, links between said support and said inner gear, and weights on said links arranged to counter-balance the centrifugal force of said inner gear, said Vinner gear being mounted to move outwardly under the effect of its centrifugal force.

6. In transmission apparatus, two cupshaped members, bolts connecting said members and holding their edges in spaced relation, aligned driving and driven shafts journaled in the ends of said cup-shaped members, an inner ygear having its center eccentrically mounted on said driving shaft and having at its periphery transverse recesses adapted to engage said bolts, and means for transferring rotational movements of the inner gear to the driven shaft. l

7. Transmission apparatus, comprising two cup-shaped members secured together at their peripheries to form a cylindrical casing, and an outer gear extending around the inner wall of said casing, aligned driving and driven shafts journaled in opposite side walls of said casing, a cage journaled on said driving shaft and keyed to the driven shaft, an inner gear cooperating with the outer gear and mounted within said cage for revolutionary movement, and a crank on the driving shaft connected with the inner gear, said inner gear being mounted to move outwardly under the eiect of its centrifugal force.

8. Transmission apparatuscomprising cooperating inner and outer gears having cooperating friction surfaces at their pitch circles, of which one is provided with spaced' transverse ridges while the other is provided with correspondingly spaced transverse grooves, means for revolving the inner gear about the axis of the outer gear, and weights arranged to counterbalance the centrifugal force of the inner gear about the axis of the outer gear, said inner gear being mounted to move outwardly under the effect of its cenf trifugal force so as to bring its friction surface into firm contact with the friction surface of the outer gear thus reducing the strain on said transverse ridges.

9. A transmission apparatus-comprising a casing, an outer gear fixed in said casing, aligned driving and driven shafts ournalled in the ends of said casing, an inner gear cof operating with said outer gear and having its center eccentrically mounted on said driving shaft, a cage journalled on one of said shafts and keyed to the other one, links connecting said cage to said inner gear and; having m hand.

y JOHN yJ. O. RULIANCICH. 

